① Understanding and controlling electronic structures are essential for selecting candidate thermoelectric materials and improving their properties. Focusing on the group of ionic transition-metal compounds, a database of key electronic structure parameters was constructed. Based on a comprehensive analysis using this database, a new design strategy for thermoelectric materials was proposed. [Journal of the American Chemical Society 144, 3590–3602 (2022), Solid State Physics 59, 21 (2024).]
② To prepare materials with desired properties, it is necessary to determine the optimal combination of multiple preparation parameters. A “closed-loop thin-film fabrication method” was developed that incorporates a machine learning-based decision-making process for parameter estimation and optimization, and succeeded in significantly reducing the number of experiments required. [Materials Today Physics 16, 100296 (2021), Applied Physics Vol. 91, No. 4, p. 224 (2022).]
③ Micro-thermoelectric devices were successfully developed using semiconductor microfabrication technology. High power density and an output voltage exceeding 0.5 V were achieved, which serves as a benchmark for powering IoT devices. [Materials Today Energy 28, 101075 (2022), Clean Energy Vol. 31, No. 11, p. 15 (2022), Applied Physics Letters 122, 243901 (2023).]